Recording medium, method and apparatus for providing management information

ABSTRACT

A recording medium, method and apparatus for providing management information are provided. The method includes grouping data of a digital data stream into a plurality of object units, and creating map information for accessing the data, wherein the map information includes time information and object unit information associated with the object units.

CROSS-REFERENCE

This present application is a continuation of U.S. patent applicationSer. No. 10/232,706, filed on Sep. 3, 2002, now issued as U.S. Pat. No.6,925,247B2 on Aug. 2, 2005, for which priority is claimed under 35U.S.C. § 120, which is a continuation of U.S. patent application Ser.No. 09/435,608, filed on Nov. 8, 1999, now issued as U.S. Pat. No.6,470,135 on Oct. 22, 2002; and this present application claims priorityof patent application Ser. No. 98-48096, filed in Korea on Nov. 8, 1998,under 35 U.S.C. § 119. The entire contents of each of these applicationsare herein fully incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and apparatus for recordingreceived digital data streams on a recording medium and creating andrecording management information pertaining to the recorded digital datastreams.

2. Description of the Related Art

In conventional analog television broadcast systems, video signals aretransmitted over the air or through cables after being AM or FMmodulated. With the recent advance of digital technologies such asdigital image compression or digital modulation/demodulation,standardization for digital television broadcast is in rapid progress.Based upon the Moving Picture Experts Group (MPEG) format, satellite andcable broadcast industry also moves towards digital broadcast.

Digital broadcast offers several advantages that its analog counterpartcannot provide. For example, digital broadcast is capable of providingservices with far more improved video/audio quality, transmittingseveral different programs within a fixed bandwidth, and offeringenhanced compatibility with digital communication media or digitalstorage media.

In digital broadcast, a plurality of programs encoded based upon theMPEG format are multiplexed into a transport stream which is thentransmitted. The transmitted transport stream is received by a set topbox at the receiver and demultiplexed into a plurality of programs. If aprogram is chosen from the demultiplexed programs, the chosen program isdecoded by a decoder in the set top box and original audio and videosignals are retrieved. The retrieved audio and video signals can bepresented by an A/V output apparatus such as a TV.

It is also possible to record the received digital broadcast signals ona storage medium instead of directly outputting the received broadcastsignals to A/V output devices. The stored digital broadcast signals canbe, edited and retrieved afterwards. For example, a digital data streamreceived by a set top box can be stored in a streamer such as a digitalvideo disk (DVD) recording apparatus after being transmitted throughcommunication interfaces like an IEEE-1394 serial bus. Later, the storeddigital data stream can be edited and transmitted back to the set topbox so that the stored original digital audio and video data can bepresented.

For the above-mentioned systems, it is necessary to develop a method forrecording a received digital data stream on a recording medium bypartitioning the received data stream into minimum presentation units,each minimum presentation unit being a data decoding unit. Unless therecorded data stream maps to random-accessible minimum presentationunits, the initial reproduction of the recorded stream after searchoperations may be imperfect.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide arecording medium, method and apparatus for providing managementinformation pertaining to recorded digital data streams.

A method for providing management information in accordance with anembodiment of the present invention includes grouping data of a digitaldata stream into a plurality of object units, and creating mapinformation for accessing the data, wherein the map information includestime information and object unit information associated with the objectunits.

A recording medium for providing management information in accordancewith an embodiment of the present invention includes a plurality ofobject units stored on the recording medium, the object unitsrepresenting groups of data of a digital data stream, and mapinformation stored on the recording medium for accessing the data,wherein the map information includes time information and object unitinformation associated with the object units.

An apparatus for providing management information according to anembodiment of the invention, includes elements for grouping data of adigital data stream into a plurality of object units and for creatingmap information for accessing the data, wherein the map informationincludes access time information and object unit information associatedwith the object units.

These and other objects of the present application will become morereadily apparent from the detailed description given hereinafter.However, it should be understood that the detailed description andspecific examples, while indicating preferred embodiments of theinvention, are given by way of illustration only, since various changesand modifications within the spirit and scope of the invention willbecome apparent to those skilled in the art from this detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention, illustrate the preferred embodiments ofthe invention, and together with the description, serve to explain theprinciples of the present invention.

In the drawings:

FIG. 1 is a block diagram of an apparatus in which the present inventionmay be advantageously practiced;

FIG. 2 is a pictorial representation showing the syntax of a digitaldata stream;

FIG. 3 is a pictorial representation showing the syntax of the recordeddata and the management information pertaining to the recorded datacreated by an embodiment of the present invention;

FIGS. 4A and 4B are flow diagrams of the method for recording digitaldata streams according to an embodiment of the present invention; and

FIG. 5 is a flow diagram of the method for searching a digital datastream recorded by an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In order that the invention may be fully understood, preferredembodiments thereof will now be described with reference to theaccompanying drawings.

FIG. 1 depicts a block diagram of an apparatus in which the presentinvention may be practiced according to an embodiment of the invention.The apparatus includes a set top box 100, a communication interface(e.g., IEEE-1394), and a streamer 200, all operatively coupled.

The set top box 100 receives transport streams encoded by systemencoders and transmitted by a plurality of broadcast stations anddemultiplexes the received transport streams. After a system decoder 120decodes the transport stream of a program tuned by a tuning unit 110, acontrol unit 140 outputs the decoded transport stream to an A/V outputdevice such as a TV set for presentation.

The set top box 100 may transmit a program chosen by a user to thestreamer 200 through an interface such as the IEEE-1394 interface sothat the transmitted program is recorded on a recording medium 230 suchas a digital video disk by the streamer 200.

In addition, as requested by a user, the set top box 100 may receive aprogram retrieved from the recording medium 230 by the streamer 200through the IEEE-1394 communication interface so that the receivedprogram can be presented on a TV set after being decoded by the decoder120.

A transport stream packet of a program stream, as shown in, e.g., FIG.2, includes a packet header and a payload, the packet header containingfields of a 8-bit sync byte, an error indication field indicative of apossible error of the packet, a PID showing attributes of the datacontained in the payload, and an adaptation field. The adaptation fieldcontains various information on the properties of the data stream, suchas a random access indicator indicating the start of a video sequenceheader which is a random access entry point.

The method for recording digital data streams in accordance with anembodiment of the present invention will now be described with referenceto FIGS. 1 and 3.

If a user's request for recording an incoming data stream tuned by thetuning unit 110 has been received, the control unit 140 of the set topbox 100 informs a control unit 250 of the streamer 200 that a recordingmode is set and begins to transfer the received digital stream to thestreamer 200 through the interface such as the IEEE-1394 interface. Thecontrol unit 250 of the streamer 200 controls a stream recording unit220 to record the received data stream on the recording medium 230. Thetransport stream packets (TS Pkt 1˜TS Pkt k) constituting the datastream are recorded on the recording medium 230 along with respectivetransport stream packet arrival times (TS APATs), wherein the transportstream packets with packet arrival times are organized in sectors on therecording medium 230.

Concurrently, the control unit 250 of the streamer 200 detects therandom access indicator contained in a transport stream packet header.If a random access indicator is detected, previously received transportstream packets and the transport stream packet having the random accessindicator are grouped into a stream object unit (SOBU). Likewise,transport stream packets received after the transport stream packethaving the random access indicator and a transport stream packet havingthe next random access indicator are grouped into another stream objectunit (SOBU). In this manner, the received data stream is recorded on therecording medium as a series of stream object units (SOBU 1˜SOBU q) asshown in FIG. 3. A stream object unit presentation time (SOBU_TM) and astream object unit size (SOBU_SZ) are created for each stream objectunit (SOBU) and recorded as management information pertaining to theassociated stream object unit, where the stream object unit size(SOBU_SZ) is expressed in terms of the number of sectors in which theassociated stream object unit (SOBU) is recorded. As shown in FIG. 3,the specific location of a desired SOBU (e.g., SOBU g) can be identifiedusing the stream object unit size (SOBU_SZ), such that the SOBU_SZ canbe considered location information.

If a predetermined number, for example 20, of stream object units(SOBUs) are created by repeating the grouping task, the control unit 250creates and records a stream object unit index number (SOBU_N), anaccumulated presentation time (ACC_TM), and an accumulated size (ACC_SZ)for the 20 stream object units. The accumulated presentation time(ACC_TM) and accumulated size (ACC_SZ) for each of 20 stream objectunits are the presentation time and size accumulated from the startposition (SOB2_OFF_ADDR) of the stream object (SOB2) containing theassociated stream object units to each of 20 stream object units,respectively. In this aspect, ACC_SZ can be considered locationinformation.

After the recording mode ends, the control unit 250 of the streamer 200groups the created stream object units (SOBUs) into a stream object(SOB) and groups the recorded accumulated sizes (ACC_SZs) and streamobject unit sizes (SOBU_SZs) into a map. The map is stored in themanagement information area of a memory 260 as stream object information(SOBI).

Subsequently, the control unit 250 of the streamer 200 creates apresentation sequence information (Cell) concerning the map and storesthe cell as the presentation sequence information corresponding to thecreated record (RCD) or program (PG) in the management information areaof the memory 260.

The method for a time search operation by a user will now be explainedby assuming that digital data streams are recorded on the recordingmedium by the aforementioned method.

If a user enters a search time (HH:MM:SS:FF) in order to search for aspecific position on the recording medium 230, the control unit 250 ofthe streamer 200 looks for a record (RCD) or program (PG) correspondingto the user's search time (HH:MM:SS:FF) with reference to the creationtimes (PG1_Create_TM, PG2_Create_TM, PG3_Create_TM) of records(RCD1˜RCD3) or programs (PG1˜PG3). Suppose the detected program is PG2shown in FIG. 3. Then, the control unit 250 looks for a Cell (Cell 2shown in FIG. 3) corresponding to the user's search time (HH:MM:SS:FF)with reference to the presentation start time (C1_S_TM, C2_S_TM, . . . ,Cn_S_TM) and presentation end time (C1_E_TM, C2_E_TM, . . . , Cn_E_TM)of each Cell contained in the detected program PG2.

Referring to the stream object information (SOBI) of the stream objectSOB2 associated with the detected presentation sequence information Cell2, the control unit 250 detects a target accumulated entry (ACC Entry,the entry shaded in FIG. 3) containing the accumulated presentation time(ACC_TM) which is closest to the difference between the user's searchtime (HH:MM:SS:FF) and the stream object start time (SOB_S_TM). Lastly,the control unit 250 detects a stream object unit (SOBU) correspondingto the stream object unit presentation time (SOBU_TM) of the streamobject unit containing the user's search time (HH:MM:SS:FF) byaccumulating stream object unit presentation times (SOBU_TMs) from thestream object unit pointed to by the detected accumulated entry (ACCEntry). The target stream object unit (SOBU) can be located by addingthe accumulated size (ACC_SZ) of the target accumulated entry (ACCEntry) to the sum of stream object sizes (SOBU_SZs) calculated from thestream object unit pointed to by the target accumulated entry (ACCEntry).

The control unit 250 controls a stream reproducing unit 240 to reproducetransport stream packets from the first sector (Sector 1) in which thedetected target stream object unit (SOBUg shown in FIG. 3) is recordedand transmit the reproduced transport stream packets to the set top box100 through the IEEE-1394 interface. The decoding operation, therefore,is performed from the transport stream packet having a random accessindicator, which means video data is reproduced from the Intra-pictureand audio data is reproduced from the first bye of a frame.

The method for recording digital data streams in accordance with anembodiment of the present invention will be described with reference tothe flow diagrams shown in FIGS. 4A and 4B.

If a user's request for recording an incoming data stream tuned by thetuning unit 110 has been received, the control unit 140 of the set topbox 100 informs the control unit 250 of the streamer 200 that arecording mode is set and begins to transfer the received digital streamto the streamer 200 through the IEEE-1394 interface (S11).

The control unit 250 of the streamer 200 controls the stream recordingunit 220 to record the data stream received through the IEEE-1394interface on the recording medium 230 (S13). The transport streampackets (TS Pkt 1˜TS Pkt k) constituting the data stream are recorded onthe recording medium 230 along with respective transport stream packetarrival times (TS APATs), wherein the transport stream packets withpacket arrival times are organized in sectors on the recording medium230.

Subsequently, the control unit 250 resets an internal register forstoring the number of transport stream packets (TS_Pkt_N) to zero (S15)and searches for a random access indicator (RAI) in the header of thefirst transport stream packet of the input data stream (S17). And thecontrol unit 250 increments the internal register value indicative ofthe number of transport stream packets (TS_Pkt_N) by 1 (S19) and checksif a random access indicator has been discovered in step S17 (S21).

In the instance where the existence of a random access indicator isconfirmed in step S21, the transport stream packets received up to thetransport stream packet having the random access indicator are groupedinto a stream object unit (SOBU) as discussed above (S23). Likewise,transport stream packets received after the transport stream packethaving the random access indicator and the transport stream packethaving the next random access indicator are grouped into another streamobject unit (SOBU).

If a stream object unit is created, the control unit 250 creates astream object unit presentation time (SOBU_TM) and a stream object unitsize (SOBU_SZ) for the stream object unit (SOBU) and stores such mapinformation in the management information area of the memory 260 asmanagement information regarding the stream object unit (SOBU).

The control unit 250 checks whether a request for terminating therecording mode has been received (S27) during the recording mode. If itis not received, the control unit 250 continues to search for a randomaccess indicator in the input data stream and initializes the number oftransport stream packets (TS_Pkt_N) (S29). And the flow returns to stepS19.

If the terminating command is received, the control unit 250 reads themanagement information stored in the management information area of thememory 260 and records the management information in the managementinformation area of the recording medium 230 before terminating therecording mode (S31).

After the recording mode ends, the control unit 250 of the streamer 200groups the created stream object units (SOBUs) into a stream object(SOB), and groups the recorded accumulated sizes (ACC_SZs), which havebeen generated during the recording mode as in the aforementionedembodiment, and stream object unit sizes (SOBU_SZs) into a map. The mapis stored in the management information area of the memory 260 as streamobject information (SOBI). In addition, the control unit 250 alsocreates presentation sequence information for the grouped stream objectand records it as cell information for the stream object.

Additionally, the control unit 250 sets the value of a stream objectunit grouping type indication flag contained in the stream objectinformation (SOBI) to 1 for indicating that stream object unitsconstituting the stream object are created based upon the random accessindicator.

The value of the stream object unit grouping type indication flagimplies that the stream object unit (SOBU) is created so that it israndomly accessible and thus the stream object unit (SOBU) is the basicgroup for a trick-play which means data-discrete reproduction. This factalso means that the stream object unit (SOBU) contains a random accessentry point.

Stream object units can be created in many different ways. For example,it is possible to generate stream object units of a predetermined sizewithout regard to the random access indicator. If a random accessindicator is detected from a stream object unit, a flag indicative ofthe fact can be set to 1 for the stream object unit (SOBU) and recordedon the recording medium.

To be more specific, an n-bit data is created for a stream objectincluding n stream object units (SOBU1˜SOBUn) and each bit of the datais associated with each stream object unit. Then, it can be examinedwhether a stream object unit (SOBU) has a random access indicator bysimply checking the associated bit value.

In the meantime, if it is verified that a random access indicator is notdiscovered in step S21, the control unit 250 checks if the number oftransport stream packets (TS_PKT_N) stored in the internal register isgreater than a predetermined value K (S33). If not, the flow returns tostep S17 and continues the aforementioned procedure.

The value K is determined in consideration of the minimum transfer rateof a data stream. For example, suppose that the desirable minimum timelength of a stream object unit (SOBU) is 0.5 s (seconds) and the minimumtransfer rate of an input data stream is 3 Mbps. In this case, the sizeof data received for 0.5 s exceeds 1875000 bytes and more than 997transport stream packets are received for 0.5 s with each transportstream packet having 188 bytes. Considering the number of transportstream packets received for 0.5 s, it is desirable to set the value Kgreater than 997. It is because at least one packet among 997 transportstream packets should have a random access indicator if the data streamis supposed to contain random access indicators.

If the number of transport stream packets (TS_PKT_N) stored in theinternal register is greater than the predetermined value K in step S33,the control unit 250 decides that random access indicators were notinserted into the data stream when the data stream was transmitted bythe associated broadcast station. The flow continues to step S35.

With reference to time information contained in the transport streampackets, the control unit 250 records the received transport streampackets by grouping them into stream object units, with each streamobject unit (SOBU) having a fixed time length, for example, 0.5 s (S35).Also, the control unit 250 creates a stream object unit size (SOBU_SZ)and a stream object unit presentation time (SOBU_TM) for each streamobject unit (SOBU) and records the created information as managementinformation for the associated stream object unit (SOBU) (S37). Thestream object unit size (SOBU_SZ) of a stream object unit (SOBU) isexpressed in terms of the number of sectors containing the stream objectunit. If 20 stream object units (SOBUs) are created after 10 s elapses,the control unit 250 creates and records a stream object unit indexnumber (SOBU_N), an accumulated presentation time (ACC_TM), and anaccumulated size (ACC_SZ) for each stream object unit (SOBU). Theaccumulated presentation time (ACC_TM) and accumulated size (ACC_SZ) ofa stream object unit are the presentation time and size accumulated fromthe start position (SOB2_OFF_ADDR) of the stream object (SOB2)containing the stream object unit to the stream object unit,respectively.

After the recording mode ends, the control unit 250 groups the createdstream object units (SOBUs) into a stream object (SOB) and groups therecorded accumulated sizes (ACC_SZs) and stream object unit sizes(SOBU_SZs) into a map. The map is stored in the management informationarea of the memory 260 as stream object information (SOBI).

At this time, the control unit 250 sets the stream object unit groupingtype indication flag contained in the stream object information (SOBI)to zero to inform that stream object units (SOBUs) constituting thestream object (SOB) have not been generated based upon random accessindicators but generated based upon time.

Subsequently, the control unit 250 of the streamer 200 creates apresentation sequence information (Cell) concerning the map and storesit in the management information area of the memory 260 as thepresentation sequence information corresponding to the record (RCD) orprogram (PG) which has been created by a single recording operation.

The control unit 250 checks whether a request for terminating therecording mode has been received (S39). If so, the flow branches to stepS31 wherein the management information (e.g., structure shown in FIG. 3and discussed above) stored in the management information area of thememory 260 is recorded in the management information area of therecording medium 230 and the recording mode terminates. If not, the flowreturns to step S35 to the aforementioned recording procedure.

If a user sets a time search mode in order to search for specific datarecorded on the recording medium by the above-mentioned method describedwith reference to FIGS. 4A and 4B, the search operation begins. Adetailed explanation about the search operation will be given below withreference to FIGS. 3 and 5 according to an embodiment of the presentinvention.

If a user enters a search time (HH:MM:SS:FF) in order to search for aspecific position on the recording medium 230 (S41), the control unit250 of the streamer 200 looks for a record (RCD) or program (PG)corresponding to the user's search time (HH:MM:SS:FF) with reference tothe creation times (PG1_Create_TM, PG2_Create_TM, PG3_Create_TM) ofrecords (RCD1˜RCD3) or programs (PG1˜PG3). Suppose the detected programis PG2 shown in FIG. 3. Then, the control unit 250 looks for a Cell(Cell 2 shown in FIG. 3) corresponding to the user's search time(HH:MM:SS:FF) with reference to the presentation start time (C1_S_TM,C2_S_TM, . . . , Cn_S_TM) and presentation end time (C1_E_TM, C2_E_TM, .. . , Cn_E_TM) of each Cell contained in the detected program PG2 (S43).

Next, the control unit 250 reads stream object unit grouping typeindication flag from the stream object information (SOBI) of the streamobject SOB 2 corresponding to the detected Cell 2 (S45) and checks ifthe flag is 1 (S47). The flag value “1” indicates that stream objectunits constituting the stream object SOB 2 have been created based onrandom access indicators (S47).

If it is confirmed in step S47 that the flag is 1, the control unit 250searches for a stream object unit (SOBUg in FIG. 3) corresponding to theuser's search time as explained with reference to FIG. 3 (S49) andcontrols the stream reproducing unit 240 so that reproduction ofrecorded data begins from the packets located in the first sector(Sector 1) containing the stream object unit SOBUg and the retrieveddata can be transferred to the set top box 100 through the interfacesuch as the IEEE-1394 interface 210 (S51).

If it is confirmed in step S47 that the flag is not 1, the control unit250 detects a target accumulated entry (ACC Entry, the entry shaded inFIG. 3) containing the accumulated presentation time (ACC_TM) which isclosest to the difference between the user's search time (HH:MM:SS:FF)and the stream object start time (SOB_S_TM) with reference to the streamobject information (SOBI) of the stream object SOB2 associated with thedetected presentation sequence information Cell 2. Lastly, the controlunit 250 detects a stream object unit (SOBU) corresponding to the streamobject unit presentation time (SOBU_TM) of the stream object unitcontaining the user's search time (HH:MM:SS:FF) by accumulating streamobject unit presentation times (SOBU_TMs) from the stream object unitpointed to by the detected accumulated entry (ACC Entry). The targetstream object unit (SOBU) can be located by adding the accumulated size(ACC_SZ) of the target accumulated entry (ACC Entry) to the sum ofstream object sizes (SOBU_SZs) calculated from the stream object unitpointed to by the target accumulated entry (ACC Entry) (S53).

As a next step, the control unit 250 detects the transport stream packetarrival time (TS APAT) of each transport stream packet from the firstSector 1 containing the detected stream object unit SOBUg and comparesthe packet arrival time with the user's search time (HH:MM:SS:FF). Thecontrol unit 250 starts to retrieve recorded data from the transportstream packet whose packet arrival time is after the user's search timeand controls the stream reproducing unit 240 so that the retrieved datacan be transferred to the set top box 100 through the IEEE-1394interface 210 (S55).

The invention may be embodied in other specific forms. For example, theinvention is not only applicable to the apparatus shown in FIG. 1 butapplicable to any system including a subsystem functioning as a set topbox, another subsystem functioning as streamer, and a communicationinterface between the two systems.

In the previous embodiments, the random access indicators contained inthe received data stream were detected by the control unit of thestreamer. It is also possible, however, for the control unit of the settop box to detect the random access indicators and transmit the detectedrandom access indicators to the streamer through the IEEE-1394interface. In this case, the control unit of the set top box detectsrandom access indication information for each transport stream packetand adds a flag indicative of the existence of the random accessindication information during time stamping of the associated transportstream packet. The control unit of the streamer checks the flag anddetermines the method for creating stream object units depending on theflag value.

According to the present invention, random access information containedin a received digital data stream is detected and stream object unitsare created based upon the detected random access information, whichenables reproduction of recorded data to start from the transport streampacket having the random access information and prevents imperfect datareproduction after track seek or time seek operations.

Also, the received digital data stream is recorded on a recording mediumby partitioning the received data stream into random-accessible minimumpresentation units or presentation units of a fixed time lengthdepending upon the existence of random access indication information,thereby not limiting the usage of the apparatus.

The invention may be embodied in other specific forms without departingfrom the sprit or essential characteristics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

1. A method of providing management information, comprising: groupingpackets of data of a digital data stream into a plurality of objectunits, and grouping one or more object units into an object; andcreating management information for accessing the data, the managementinformation including a map information and an indication information,wherein the map information includes an object unit index tableassociated with the object units, and the object unit index tableincludes object unit size information associated with each of the objectunits, and wherein the indication information indicates whether the datapacket are grouped into the object units on a basis of either apredetermined time period or an entry point information included in thedigital data stream.
 2. The method of claim 1, wherein the object unitindex table further includes object unit presentation time informationassociated with each of the object units.
 3. The method of claim 1,wherein each object unit comprises a stream object unit (SOBU), whichcomprises one or more data packets, and the object comprises a streamobject (SOB).
 4. The method of claim 1, wherein the managementinformation is included in stream object information (SOBI) associatedwith the object.
 5. The method of claim 1, further comprising: recordingthe management information in a storage.
 6. The method of claim 5,wherein in the recording step, the storage is either an internal memoryor an optical disc.
 7. The method of claim 1, further comprising:creating a presentation sequence information concerning the mapinformation.
 8. The method of claim 1, wherein the entry pointinformation is associated with a position of specific video data.
 9. Themethod of claim 8, wherein the specific video data is an Intra (I)picture.
 10. A recording medium providing management information,comprising: at least one object comprising a plurality of object unitsstored on the recording medium, each of the object units having one ormore packets of data of a digital data stream; and managementinformation stored on the recording medium for accessing the data, themanagement information including a map information and an indicationinformation, wherein the map information includes an object unit indextable associated with the object units, and the object unit index tableincludes object unit size information associated with each of the objectunits, and wherein the indication information indicates whether the datapackets are grouped into the object units on a basis of either apredetermined time period or an entry point information included in thedigital data stream.
 11. The recording medium of claim 10, wherein theobject unit index table further includes object unit presentation timeinformation associated with each of the object units.
 12. The recordingmedium of claim 10, wherein each object unit comprises a stream objectunit (SOBU), which comprises one or more data packets, and the objectcomprises a stream object (SOB).
 13. The recording medium of claim 10,wherein the management information is included in stream objectinformation (SOBI) associated with the object.
 14. The recording mediumof claim 10, wherein the recording medium is an optical disc.
 15. Anapparatus for providing management information, comprising: a formatterfor grouping packets of data of a digital data stream into a pluralityof object units, and grouping one or more object units into an object;and a controller for creating management information for accessing thedata, the management information including a map information and anindication information, wherein the map information includes an objectunit index table associated with the object units and the object unitindex table includes object unit size information associated with eachof the object units, and wherein the indication information indicateswhether the data packets are grouped into the object units on a basis ofeither a predetermined time period or an entry point informationincluded in the digital data stream.
 16. The apparatus of claim 15,wherein the object unit index table further includes object unitpresentation time information associated with each of the object units.17. The apparatus of claim 15, wherein each object unit comprises astream object unit (SOBU), which comprises one or more data packets, andthe object comprises a stream object (SOB).
 18. The apparatus of claim15, wherein the management information is included in stream objectinformation (SOBI) associated with the object.
 19. The apparatus ofclaim 15, further comprising: a recording unit for recording themanagement information in a storage.
 20. The apparatus of claim 19,wherein the storage is either an internal memory or an optical disc. 21.The apparatus of claim 19, wherein the controller further creates apresentation sequence information concerning the map information.
 22. Amethod of providing management information, comprising: reading amanagement information for accessing a digital data stream, the digitaldata stream comprising one or more packet groups including a pluralityof packets respectively, one or more packet groups grouped into anobject unit, and one or more object units grouped into an object,wherein the management information includes a map information and anindication information, the map information including an object unitindex table associated with the object units, the object unit indextable including object unit size information associated with each of theobject units, and the indication information indicating whether thepacket groups are grouped into the object units on a basis of either apredetermined time period or an entry point information included in thedigital data stream; identifying the indication information to identifywhether the digital data stream is recorded on the basis of thepredetermined time period or the entry point information; andcontrolling a reproduction mode based on the result of the identifyingstep.
 23. The method of claim 22, wherein the reproduction mode is amode for reproducing data recorded at a specific location of a recordingmedium.
 24. The method of claim 23, wherein the controlling stepcontrols the reproduction mode using the map information with a packetarrival time, if the identifying step identifies that the digital datastream is recorded on the basis of the predetermined time period. 25.The method of claim 23, wherein the controlling step controls thereproduction mode using the map information without a packet arrivaltime, if the identifying step identifies that the digital data stream isrecorded on the basis of the entry point information.